Is Viagra the World's Most Popular Male Sexual Performance Drug?

12 studies have the 'user satisfaction' answer

In four studies where couples used Viagra, then Cialis (or vice versa), the women strongly preferred the latter.

En español | In the pantheon of globally recognized brand names, Viagra is right up there with Coca-Cola and Rolls-Royce.

In terms of user satisfaction, however, Viagra (sildenafil) runs a distant second to Cialis (tadalafil).

I found 12 studies — none of them funded by the drug companies themselves — in which men from various countries tried both drugs and then reported which one they chose to continue. It was a shutout: Cialis 12, Viagra 0. And the 8,300 participants favored Cialis by a wide margin — 3 to 1, on average. In studies that also included the third major erection drug, Levitra (vardenafil), Cialis was still substantially more popular than either competitor.

Women also prefer Cialis. In four studies where couples used Viagra, then Cialis (or vice versa), the women strongly preferred the latter.

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Whence this bedroom-centric brand loyalty? Simple: Cialis lasts longer. Viagra and Levitra are effective for approximately four hours, Cialis for 36. If a man takes Cialis on Friday evening, he can count on erection assistance through part of Sunday. Both men and women say they like the fact that Cialis allows them to take their eyes off that ticking clock and make love whenever they wish. So for dating couples or new lovers who prize sexual spontaneity, Cialis has a clear advantage.

Oddly, Cialis is favored by a less sexually impulsive group as well: long-term spouses, who are likelier to schedule sex dates. The drug's more wide-open window of opportunity apparently makes for friendlier spousal negotiations over time and place.

Drug similiarities and differences

Except for their duration of action, all erection medications function in similar fashion. They begin to work in about an hour. They work equally well if taken on an empty stomach or after a meal. None produce spontaneous erections, so no mortifying bulges in the produce aisle; they enhance firmness only in the context of erotic stimulation. Their side effects are quite similar, too: headache (16 percent of users), upset stomach (7 percent) and nasal congestion (4 percent). (Important note: Never use erection medications if you're taking nitroglycerin for angina; the combination can be fatal. Remember how close we came to losing Jack Nicholson in Something's Gotta Give?)

And you might be surprised to learn how few older men use any erection drug at all: Sales of "vitamin V" have never reached more than about half of what experts predicted when such medications were first approved in 1998. When Cornell researchers surveyed 6,291 older men on the subject, 48 percent reported some degree of erectile dysfunction, but only 7 percent had ever tried an erection drug.

Why so few? One reason is that, compared with women, men are less willing to take medication.

But the main reason is that the drugs enhance intercourse, whereas older couples generally evolve away from the old in-out toward hand massage, oral sex and vibrator play. A "fact of life" for many older lovers is that intercourse is a hassle. Even with drugs, erections may be iffy; even with lubrication aplenty, vaginal dryness or atrophy may cause pain during intercourse. That's why many older lovers move on from intercourse to other pleasures. And if you're no longer having intercourse, erections aren't necessary, so why take a drug?

In addition, men don't need erections to have orgasms. You read that right: Given sufficient fondling, a man can have a marvelous orgasm with a semifirm or even flaccid penis.

Among men who try erection medications, only half refill their prescriptions. Why? Effectiveness, for starters. The manufacturers claim the drugs are 70 to 85 percent effective, but research shows their effectiveness to be more in the 50 to 60 percent range; for men with diabetes, heart disease, or high cholesterol or blood pressure, it can be even lower. And wait until you hear how the studies define "effectiveness": We're not talking rock-hard porn-star erections here, but rather any increase in firmness that enables intercourse. That means even drug-fueled erections can be on the soft side, leaving many men feeling disappointed.

Bottom line: If you've never tried an erection medication, you're in the majority. But if you use one, you — and your partner — will likely be happiest with one that lasts the longest. For now, according to the latest surveys, that's Cialis.